Seaport Transportation

[F-Line to Dudley]

Re: Track 61 (Seaport - Back Bay DMU)

Well, you don't dig up the streets just to fix utilities. When you are done you have a subway which:

A) Links green line central subway to SS (CR, Amtrak)

B) Adds a red-green transfer to lighten the load on Park

C) Knits together a zillion of Boston's major business, hotel, tourist and entertainment districts (LMA, Fenway, BB, Theater, FiDi, Waterfront) with a single transfer to absolutely everywhere.

The question is: when you factor the benefits of fixed utilities into the equation, does the price of the subway look more attractive.

It didn't with SL Phase III. So that is a known-known here. The wider BRT tunnel didn't kill it. It was going to be crappy speed, a much longer tunnel than LRT, tear the living shit out of the Common, and require an entirely new Boylston station to be built underneath the existing one. But the utility relocation and building foundation mitigation was the killer, and that would've been the same with an LRT tunnel.


Like I said before, if they want to get this done in our lifetimes they have to choose the recycle/reuse trajectory that sticks to as much existing subway infrastructure as possible; doubles up the usage of as much infrastructure as possible (i.e. provisioning for Washington St. light rail); and cuts-and-covers under as high a % of pre-cleared, well-documented urban renewal land as possible. That means Tremont Tunnel to South End, existing Boylston station with no greater impacts than taking down the platform fences and ADA'ing it, the blocks around Tufts that were all blowed up in the 60's, and the Pike Canyon/NEC/Marginal Rd. that were all totally made over in 1965. Take your best shot at a trajectory from one side of the Pike canyon or the other. There's quite a few ways to slice and dice it.

But give up the notion that a direct, straight-line shot is ever going to possible with enough brainstorming. It's been brainstormed many times before. And it gets stopped dead by the same problems that completely and totally overwhelm the value of constructing any tunnel through there. That cost vs. benefit calculation has pretty much been answered. The fact that there are orders-of-magnitude cheaper connections like the reuse-on-roundabout-routing Tremont/South End trajectory that still makes good time to the Transitway and still hit Orange transfers en route deflates the last "at any cost" arguments of doing a manifest destiny dig on a straight line.

Besides, with how dog-slow the Silver Line turned out to be through the Transitway I bet an LRV through the South End still matches or beats the defective-by-design Phase III BRT tunnel. So a mapmaking compromise is still going to perform with better travel time and capacity than the actual monstrosity they were all set to build us on a "direct" routing.

 

[dagger]

Re: Track 61 (Seaport - Back Bay DMU)

Has it occurred to anyone else that this project may be extended to the Grand Junction Branch? It would be a first step to the Urban Ring

 

[Matthew]

Re: Track 61 (Seaport - Back Bay DMU)

I think some of us have thought about extending it to Brighton or Newton. To do the Grand Junction you would need a new track connection to avoid a direction change.

 

[wicked]

Re: Track 61 (Seaport - Back Bay DMU)

Besides, with how dog-slow the Silver Line turned out to be through the Transitway

Why are buses restricted to such low speeds in the tunnel? The curves don't seem that sharp.

 

[George_Apley]

Re: Track 61 (Seaport - Back Bay DMU)

Not really wanting to go off-topic, but I really like to know. What you just framed was a huge amount of cost and energy to document over decades for the gains of a few shorter power outage a year. That can be imagine hundreds to thousands of hours of collective disruption for decades to save a few hours a year. Unless you left something out, it does sounds like a reasonable calculation that the costs outweighs the gains (sadly).

It might very well make a lot of sense to do it if you factor it all together. Try to convince the public and the politicians of that though.

 

[George_Apley]

Re: Track 61 (Seaport - Back Bay DMU)

Why are buses restricted to such low speeds in the tunnel? The curves don't seem that sharp.

I believe it's because the tunnels have no signals.

 

[F-Line to Dudley]

Re: Track 61 (Seaport - Back Bay DMU)

I believe it's because the tunnels have no signals.

And the articulateds did not prove to be quite the nimble-turning sports cars they hoped they would be in the initial design.

Plus the awful condition of the decaying pavement has led to creeping speed restrictions in the decade since it opened. That one has zero excuses. You get the service your maintenance practices pay for.

 

[davem]

Re: Track 61 (Seaport - Back Bay DMU)

I believe it's because the tunnels have no signals.

Also driver sneezes really hard and scrapes the wall is a fear I'd imagine.



F-line: what is the theorized routing for your plan?

Union Sq / Tufts - Seaport seems the obvious way, but then you miss a straight shot into the back bay, the whole reason the BCEC wants this shuttle.

If you build the connection to the E and send every other train to the seaport you get crappy headways due to street running and would really oversaturate that line. Logistically it might be hard too due to lack of yard space to support it (unless they build a layover around the design center).

If you build the D-E connector and run Riverside - Seaport you piss off a lot of people in newton who just lost a one seat ride to downtown. It might make up for it with the early connection to the orange line however.

I guess you could also create a new route Reservoir - Seaport (or even BC - Seaport via CH Ave) which may be the best way to not piss people off. But you would still need to do the D-E, which expands the scope of the project considerably.

(on my phone, excuse spelling errors)

 

[Shepard]

Re: Track 61 (Seaport - Back Bay DMU)

Maybe I don't get the track layout, but couldn't an eastbound central subway train turn right at Boylston to go under Tremont and out to the NEC, and vice versa?

 

[winstonoboogie]

Re: Track 61 (Seaport - Back Bay DMU)

I believe it's because the tunnels have no signals.

Correct, a decision was made early on to depend on line of sight operation without signals. Given the close stop spacing in a short distance, the modeling found there was actually very little trip time improvements if signals were installed.

 

[davem]

Re: Track 61 (Seaport - Back Bay DMU)

The way boylston is configured you can go N-S, S-N, S-W, or W-N. If that makes sence. Basically coming off boylston you can only hang a left, not a right.

 

[bigeman312]

Re: Track 61 (Seaport - Back Bay DMU)

The way boylston is configured you can go N-S, S-N, S-W, or W-N. If that makes sence. Basically coming off boylston you can only hang a left, not a right.

And N-W

 

[Shepard]

Re: Track 61 (Seaport - Back Bay DMU)

The way boylston is configured you can go N-S, S-N, S-W, or W-N. If that makes sence. Basically coming off boylston you can only hang a left, not a right.

Yikes, then I don't get F-Line's vision either

 

[F-Line to Dudley]

Re: Track 61 (Seaport - Back Bay DMU)

Also driver sneezes really hard and scrapes the wall is a fear I'd imagine.



F-line: what is the theorized routing for your plan?

Union Sq / Tufts - Seaport seems the obvious way, but then you miss a straight shot into the back bay, the whole reason the BCEC wants this shuttle.

If you build the connection to the E and send every other train to the seaport you get crappy headways due to street running and would really oversaturate that line. Logistically it might be hard too due to lack of yard space to support it (unless they build a layover around the design center).

If you build the D-E connector and run Riverside - Seaport you piss off a lot of people in newton who just lost a one seat ride to downtown. It might make up for it with the early connection to the orange line however.

I guess you could also create a new route Reservoir - Seaport (or even BC - Seaport via CH Ave) which may be the best way to not piss people off. But you would still need to do the D-E, which expands the scope of the project considerably.

(on my phone, excuse spelling errors)

I don't think you can build the Boylston-Transitway and BBY bypass of Copley Jct. at the same time or same funding commitment. It's way too scary a price tag and construction scale to swallow in one bite. Those are separate projects you have to stage out as part of some multi-decade vision for LRT in Boston. Real long-term commitment stuff.

What I'm thinking as an initial build is:

1) Do the tunnel reactivation with Tufts station under the park.

2) Since the tunnel's a 4-tracker to the old portal, build the Tufts station as a 4-tracker right off the bat. That way you have a second set of platforms that can be used immediately as a stub turnback while the other set sees thru service. With this you can turn trains coming from the north through every single downtown transfer station instead of missing Red by turning at Brattle Loop or being permanently consigned to a hard-to-dispatch Medford-Riverside marathon. And get an OL transfer at the last stop that also helps OL traffic a lot by hitting it on both sides of the State-DTX choke point via Haymarket and Tufts. You can either do this platform configuration as stub-end, or take the profile of the park and the old 'pit' incline and craft a turning loop. It would be less sharp a loop angle than Park St. loop by a good margin.

3) +2 blocks of tunneling under Shawmut and the Pike/NEC. The urban renewal blast zone where the utilities are all mid-60's known-knowns. Portal up from the NEC on the Herald St. wall to the Washington/Herald intersection on one signal phase.

4) Find your surface-level trajectory to SS and the grassy plaza along the bus terminal. Multiple options, some more grade-separated than others.

5) Portal-under shallow on the plaza next to the bus station. Tunnel roof just 3-6 ft. below and supporting nothing but grass and park benches...i.e. a far less invasive Fields Corner-Ashmont air rights cover-over and not a street cut-and-cover that's 25+ feet down with all utilities sandwiched between roof and street. However far along the plaza 93 descends ultra-deep, start the incline down to the Transitway's level. Make the sharp turn at the Summer St. intersection and merge into the busway pavement. Buses still loop at SS, trolleys loop at SL Way with a small layover yard, both modes overlap the length of the Transitway.

6) Choose your adventure on routings. I think this works well length-wise as the permanent Medford routing, since Union is currently assigned to be the E's terminus. You could easily supplement at rush-hour with a SL Way-North Station short turn for extra coverage of all the critical transfers and truncate Medford at Tufts loop. Doesn't really matter...you can go anywhere-to-anywhere from Boylston inbound. Tufts is critical for getting you efficiently to BBY. You don't have the direct routing yet because that's a separate build, but a one-stop hop on uncongested portions of Green and Orange is the next best thing to tide you over until later builds are fundable.



Now you are pre-provisioned for later-funded builds to:
-- Add Washington St. light rail off the portal.
-- Relocate the E off Copley Jct. to a BBY subway off Tufts dug under Marginal St. (with relatively easy sideways access through the Pike retaining wall), and use the other 2 platforms for that service.
-- Thru-route that BBY route to the Seaport by using the Tufts loop track. Build a small third platform on that basically completing its ultimate configuration as a Gov't Ctr.-shaped wedge. i.e. the loop track can now act as both a loop and a wye.
-- A real grade-separated subway to SS bootstrapped onto the N-S Link NEC leads. Since that RR tunnel will portal up to the surface at the Washington St. overpass in the same exact spot as the GL portal is spitting out in the opposite direction, all you have to do is shiv a track split underground right before the Washington St. trolleys spit on the surface and keep going under the NEC until the Harrison block for this relocated SS subway routing. Then when the Link tunnel is a safe distance underground, piggyback on top of it on an upper level for the trip to SS. Peel off that tunnel it before the Link crosses under the surface wye to the opposite side of the station. Short cut-and-cover under the dead-end stub of Kneeland, then under the grassy plaza at shallow level. Seal your previously built portal, abandon the surface routing, and join the end of the new tunnel with your previously existing one.
-- Various and sundry Urban Ring routings from the Lechmere end.
-- Various and sundry D, Kenmore-end Urban Ring, and future Needham Jct. branch routings when the Huntington Subway is extended contiguously to Brookline Village, giving you an entire second downtown trunk to the Central Subway.


One build--Tremont tunnel reactivation, Tufts station under Eliot Norton Park pre-provisioned for 4 tracks and a loop, 2 blocks of urban renewal cut-and-cover to a Washington/Herald portal--provisions you for six GRAND-scope future builds utilizing this relatively cheap infrastructure to the hilt. You don't get quite this much future flex barreling through Chinatown at $4B. So think far future for what the recycle/reuse/double-up build gets you despite the roundabout routing and try to de-couple too many of these projects from being built and paid for at once. The Boston Transit Commission truly had it right in 1898 when they built that tunnel and the 'pit' portal spanning an entire South End block. Today they need to re-discover just how right their forefathers got it as an effective downtown circulator.


EDIT: I'll post a map of this grand pan-LRT vision sometime. I've had one half-finished sitting on my Google account for like a year now, and it color-codes the segments to break out what the individual builds are to gradually turn the Green Line over time into a real inner core circulator instead of the square-peg half solution it is now. I gotta wait for a rainy weekend or something to finish it. It's less a Crazy Transit Pitches kitchen sink monstrosity than highlighting the individual additions you can make to add more circulating scale. There's waaay more additions than can feasibly be built, way more than will give the network any tightly-focused core purpose, and even the more useful ones can't all be built in less than 30 years. But by highlighting the pieces it puts a visual to the debate of prioritizing what should go first, what's most mission-critical, and what's simply a nice-to-have surplus to requirement that we shouldn't worry too much about with finite resources to spend. And that's probably more useful for debating stuff like quickest way of fixing the SL missing link soon.

 

[novitiate]

Re: Track 61 (Seaport - Back Bay DMU)

I don't think you can build the Boylston-Transitway and BBY bypass of Copley Jct. at the same time or same funding commitment. It's way too scary a price tag and construction scale to swallow in one bite. Those are separate projects you have to stage out as part of some multi-decade vision for LRT in Boston. Real long-term commitment stuff.

I know that you've said before that part of the issue is the actual BBY-Copley Jct. part, because of buildings in the area. Would a (temporarily) stub-end station at BBY be more affordable? (Thinking of a Union-Porter type situation) Or does the expense come from doing anything in the BBY area at all?

 

[F-Line to Dudley]

Re: Track 61 (Seaport - Back Bay DMU)

I know that you've said before that part of the issue is the actual BBY-Copley Jct. part, because of buildings in the area. Would a (temporarily) stub-end station at BBY be more affordable? (Thinking of a Union-Porter type situation) Or does the expense come from doing anything in the BBY area at all?

Not necessarily. You can't interface with BBY station without hitting the tougher going at Trinity Pl. on the Pike air rights, so any build has the same challenge once it crosses under Clarendon St. If you're going to go two-thirds of the distance to the Huntington tunnel on an easy dig, what difference does stopping 300 ft. past Clarendon at a stub make vs. 1500 ft. to the Huntington tunnel? If you're already ripping the ground open that's negligible aggravation for a very very big difference in functionality. And you certainly wouldn't want to go back here a second time to rip things back open.

The way to do it is threading onto the Trinity Pl. side of the parking garage, where it keeps along the Pike underground and steers clear of the entrance ramp under the garage. The space is likewise accessible through the Pike retaining wall, and the advancing tunnel construction here would simply need to reinforce that air rights load-bearing retaining wall separating the subway from the Pike. If anything on the parking garage has to get underpinned, let it be the two circular access ramps sticking off the north side of the building. And let any other building impact mitigations be limited to the far SW corner of the John Hancock hotel where Trinity Pl. snakes around as a narrow back alley. Once you're at Dartmouth it's pretty smooth sailing under 1 block of Stuart and 1 block of Huntington that were all ripped up and reconfigured when the Mall air rights were added.


It's not cheap on those last 3 blocks (but very cheap the whole distance between Tufts station and Clarendon), but the disrupted area is 1980's construction air rights over a 1965 cut that nuked the surrounding blocks. If it has to be an invasive job, make it short like this and make it through 100% documented known-knowns underground. That's a build you can accurately pin a cost and difficulty to without uncapped bloat.

 

[davem]

Re: Track 61 (Seaport - Back Bay DMU)

Im comming around to your plan f-line. I forgot about the orange line transfer for some reason, that's huge. This way, even though its not a one seat ride bcec-copley area, you've got two ways to get there, the ol @ tufts or the gl @ boylston.


The only real issue now is the super-future if the green line gets converted to heavy rail. Without an essex st subway, the boylston subway will have to perpetually deal with the curve. Any idea if blue line trains could negotiate it?

 

[F-Line to Dudley]

Re: Track 61 (Seaport - Back Bay DMU)

Im comming around to your plan f-line. I forgot about the orange line transfer for some reason, that's huge. This way, even though its not a one seat ride bcec-copley area, you've got two ways to get there, the ol @ tufts or the gl @ boylston.


The only real issue now is the super-future if the green line gets converted to heavy rail. Without an essex st subway, the boylston subway will have to perpetually deal with the curve. Any idea if blue line trains could negotiate it?

Blue cars can because Bowdoin Loop is an ex- trolley loop tighter radius than Boylston curve. But there's not a compelling need to convert the Central Subway to heavy rail. That movement was a little blip on the radar in the 1920's after the Riverbank subway was cancelled and before the Depression when they needed a way to get large-capacity rapid transit west of downtown but couldn't take any RR ROW capacity from the private RR's that were at their peak. Once the Depression, WWII, and collapse of the RR's happened that stopped being a consideration. The 1945 plan was pretty much a giant ROW grab from the failing RR's.

If there needs to be another downtown HRT flank, that's what half of the N-S Link and/or the Storrow roadbed is for. Green's future is more as radial circulator in the core with an Urban Ring-ier and Silver Line-ier tinge, and neighborhood branches where there needs to be endpoint branches. The difference here is the gradual buildout of a completely parallel trunk subway stretching from Brookline Village to BBY to the Tufts wye to SS to the Seaport that can be equally load-bearing in its own right while having multiple cross routings to the existing downtown transfers. Which becomes 2-1/2 load-bearing trunks when UR Grand Junction between a BU Bridge-buried B and Lechmere gets factored in. Then you can do equal parts circulator service patterns and B/C/Arborway/Oak Sq. -esque neighborhood branches.

The thing it has to stop being is another Red Line. The whole world can't ride from Kenmore to GC on one trolley in one tunnel. The BTC in all its unusually prescient foresight never EVER designed it to do that. It designed it for exactly that circulator/distributor role it needs to morph back to.

 

[George_Apley]

Re: Track 61 (Seaport - Back Bay DMU)

Yikes, then I don't get F-Line's vision either

I know F-Line explained it (again) in detail, but my fantasy map largely corresponds to it.

It's like this:

You ultimately get to BBY via a new tunnel from Tufts to BBY, which then joins the Huntington Ave subway. As part of a phased build, before the Tufts - BBY leg is done, you would have a transfer from Green at Boylston and a transfer from Orange at Tufts.

 

[F-Line to Dudley]

Re: Track 61 (Seaport - Back Bay DMU)

I know F-Line explained it (again) in detail, but my fantasy map largely corresponds to it.

It's like this:

You ultimately get to BBY via a new tunnel from Tufts to BBY, which then joins the Huntington Ave subway. As part of a phased build, before the Tufts - BBY leg is done, you would have a transfer from Green at Boylston and a transfer from Orange at Tufts.

Bingo. And these are the service patterns these build-outs get you.


With basic Tufts-->SS surface-->Transitway leg:
-- Downtown via Boylston/Tufts to SS/Seaport
-- Downtown via Boylston to Tufts loop (short-turn for max density at the transfer stops)

With basic Tufts-->SS surface-->Transitway leg, adding Washington St. LRT conversion from the Pike portal:
-- (all of the above routings)
-- Dudley to Tufts to Downtown (default route)
-- Dudley to Seaport direct (secondary route as envisioned by SL Phase III)


Adding Tufts-->BBY-->Prudential tunnel leg and bi-directional running at Tufts wye/loop:
-- (all of the above routings)
-- Heath to Back Bay/Tufts to Downtown (new default route)
-- Heath to Back Bay/Tufts to SS/Seaport (alt route)
-- Heath to Copley Jct. to Downtown (service disruption backup route or rush hour supplemental)

Assume simple D-to-E surface connecting trackage exists by this point (they can to it today with only $5-8M), so also add to all of the above upon completion of the Tufts-->BBY-->Prudential tunnel:
-- Riverside to BBY/Tufts to SS/Seaport (alt thru route via Tufts wye)
-- Riverside to BBY/Tufts to Downtown (alt route)
-- Riverside to Copley Jct. to Downtown (service disruption backup route)
-- BC via Reservoir to any of the above Riverside inbound routings (alt routing, special events)
-- Dudley to Tufts to Brookline Village to Kenmore (alt route for Red Sox games, LRT route for inner half of 66 bus)
-- "Downtown Loop": GC to Kenmore to Brookline Village to BBY/Tufts to GC (Red Sox games and other alt routes).
-- Kenmore to Seaport: Kenmore to Brookline Village to BBY/Tufts to SS/Seaport (alt thru route via Tufts wye for Red Sox games)



The surface D-to-E and surface South End-SS routings won't have infinite capacity, so when the pick-your-spots alt routing capacity is exhausted now it's time to start burying some of these surface connections in real subways.
-- Bury the E from Northeastern to Brookline Village.
-- Bury the surface South End-SS route in a piggyback build with the N-S Link's NEC portal tunnel.

Now it's a 100% subway second Central Subway.


Here's the universe of other routings that will work with 2x the downtown Green Line capacity:
-- Forest Hills streetcar to Brookline Village to anywhere inbound.
-- Needham Jct. to to Brookline Village to anywhere inbound.
-- Urban Ring Airport LRT to Lechmere to anywhere inbound.
-- Urban Ring south streetcars: Dudley-Brookline Village to anywhere inbound and/or Dudley-Transitway (via Melnea Cass, etc.) to anywhere inbound.
-- Southie streetcar branches via Transitway to anywhere inbound.
-- Further capacity for Medford branch extension.
-- Further capacity for A-line/Oak Sq. restoration.
-- Watertown via Porter/Union to Lechmere to anywhere inbound.
-- Waltham via Porter/Union to Lechmere to anywhere inbound.


Urban Ring Grand Junction is in the mix, too. Subway to BU Bridge and split with the B, reconfiguration of Kenmore loop into a B-to-D boomerang. Now you have a third complete circuit through Cambridge to load spread some more, enabling:
-- (more capacity and alt routing options for all of the above)
-- Urban Ring Cambridge: Lechmere inbound to anywhere. BU Bridge inbound to anywhere.
-- Urban Ring Harvard Branch (from the official UR proposal): BU bridge inbound to anywhere. Lechmere inbound to anywhere.




Just to give you some picture of how massively scalable this starts getting after you build every discrete little piece of these connections. And it's not very much tunneling at all if you separate each piece into a separate job:

first. . .
-- Eliot Norton Park to Pike portal
-- SS surface portal into Transitway

next. . .
-- Eliot Norton Park to BBY/Huntington tunnel

sometime later TBD...
-- Northeastern to Brigham Circle under the reservation
-- Brigham Circle to Brookline Village street cut-and-cover

sometime later TBD...
-- Kenmore to BU Bridge under the reservation (for Grand Junction tie-in)

sometime later TBD...
-- bootstrap onto the N-S Link NEC lead to join the Pike portal and the SS/Transitway portal with contiguous tunnel


Do in whatever order you see fit, but of all of these only that last one with the outright project dependency on the N-S Link is in any way an iffy prospect. Only because of the Link project dependency, only because there's some cost efficiency in combining Link + GL builds if you're blowing multiple $B's on the Link, and only because you would not want to build it alone and somehow block the path of that Link portal.

But that's it. Except for the Brigham Circle-Brookline Village job under Huntington in outside-downtown density, all of these are very short segments under post-'65 urban renewal land or cuts under an existing trolley reservation. You could reliably do EVERY dig on this list excepting maybe that Link-piggyback together inside the original price tag for that one single SL Phase III BRT tunnel through Chinatown. That's how much traffic scale and future flex the recycle/reuse/double-up plan buys you, and how much picking your spots with easy-dig land buys you. Not to mention breaking this up into small, easy-to-fund pieces instead of thinking in a monolith, and spreading these builds over a few decades with continuous commitment over those few decades...instead of this cut-and-run bullshit that's left us with a half-complete and crippled Silver Line.